Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

What is the importance of iron in diet, Q. What is the importance of iron i...

Q. What is the importance of iron in diet? What is the disease caused by iron deficiency? Iron acts as a constituent of the hemoglobin molecule and of enzymes of the energetic

Describe technique operation prosthetic valve endocarditis, Describe the Te...

Describe the Technique of Operation in prosthetic valve endocarditis? The operative principle is drainage of abscess, removal of debris and valve rep or replacement to reverse

What is the typical feature of the epithelia, Q. What is the typical featur...

Q. What is the typical feature of the epithelia? How different is it from the connective tissue? The typical feature of the epithelium is the almost absence or absence of space

Calcium requirements of school children and adolescents, Determine Calcium ...

Determine Calcium requirements of school children and adolescents? Calcium requirements in children and adolescents can be calculated on the basis of Calcium accretion during g

Stem - plant growth substances, Stem - Plant Growth Substances The rol...

Stem - Plant Growth Substances The role of auxins, cytokinins, ethylene and abscisic acid in controlling the apical bud dominance and lateral bud dormancy (Apical Dominance) a

What are muscle tissues, What are muscle tissues? How is the function of th...

What are muscle tissues? How is the function of this tissue related to the typical characteristics of its cells? Muscle tissues are tissues made of cells able to perform contr

Soil temperature, Soil Temperature Soil temperature is known to influe...

Soil Temperature Soil temperature is known to influence water absorption and ultimately transpiration to a considerable extent. In many plants water absorption is reduced shar

Protozoa, Advantages and disadvantages of protozoa

Advantages and disadvantages of protozoa

What are deciduous trees, What are deciduous trees? Deciduous trees are...

What are deciduous trees? Deciduous trees are plants that lose their leaves in a period of the year. In the case of the deciduous trees of the temperate forest the fall of the

Biotic potential of a bacterial population, Q. How different is the growth ...

Q. How different is the growth according to the biotic potential of a viral population from the growth according to the biotic potential of a bacterial population? The growth c

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd